Orlando's LED streetlights let stars shine a bit brighter

In a truly dark sky, meteors scorch the blackness every few minutes, satellites race by in all directions and the dazzling Milky Way appears as an electrified cloud.

None of those things is visible from Orlando because its urban lighting smudges the celestial scenery.

But the city has started upgrading 14,000 neighborhood streetlights, removing lamps that bathe ground and sky with a gauzy gloom. In their place are new fixtures that cast crisp illumination on the ground only. And that could be good news for sky gazers.

"I don't think the night sky should be looked at as just a playground for astronomers," said Bob Guzauskas, a member of the Astronomical Society of the Palm Beaches and an avid foe of light pollution in Florida. "It's something that is part our nature."

Providing a better view of the night sky isn't the reason Orlando Utilities Commission is spending $4.9 million to replace a type of streetlight in use for the past half-century. The switch is meant to cut costs.

The old, "sodium-vapor" streetlights run on 120 watts each, while the new, light-emitting-diode lights use 55 watts. The sodium variety puts out twice the light of an LED, but much of it is wasted, flung into outer space. LEDs aim their luminosity precisely, which allows them to appear brighter.

Los Angeles was the world's first metropolis to make a wholesale switch to LEDs, setting out in 2009 to convert 140,000 streetlights for $57 million. "There's no question that … we've seen a major improvement in light pollution," said Ed Ebrahimian, director of the Southern California city's streetlights bureau.

Among the few major U.S. cities that have followed suit: Seattle, Boston, Las Vegas and now Orlando. Within Florida, only a handful of smaller communities in the Keys and elsewhere have also made the transition. The city of St. Cloud, which gets its power from OUC, is getting the new lights as well.

OUC started testing LEDs in 2010, installing 52 in Orlando's downtown Thornton Park neighborhood. Each cost $600. Now they cost a third as much and are expected to get even cheaper.

"Rather than rushing to buy 14,000 lights, we're taking a phased-in approach, over five years, to take advantage of prices going down," said Ken Zambito, OUC's director of energy delivery.

Bottom line: OUC bills the city $8.95 a month for the power and upkeep of a sodium light. The charge for an LED will be $6.58.

Lower costs are driving streetlight conversions, but the perks of the changeover are significant and applauded.

Your corner streetlight, if a vintage model, may not be harming you in a measurable way. But it can add to the urban grunge; just as pavement entombs the natural world, light pollution walls off the heavens.

A study in 2001 estimated that more than two-thirds of Americans could no longer see the Milky Way, Earth's home galaxy, which for millenniums has prompted observers to muse about the meaning of human existence.

Most cities have spoiled their night skies.

"Light pollution follows population," said Constance E. Walker, a scientist at the National Optical Astronomy Observatory in Arizona.

The problem is worse in the more populated eastern half of the nation, where urban glare overlaps. It is even more dismal in the Southeastern U.S., where high humidity thickens the visual gravy of light pollution.

In a dark sky, a couple of thousand stars wink back at the naked eye.

But from the Orlando Science Center observatory on the north side of downtown, the stars sometimes number in the dozens. What's left to observe through the center's telescopes are celestial big boys such as Venus, Saturn and the brightest star, Sirius.

"The sky kind of disappears for us some nights," said Carl Darden, the center's lead astronomy educator.

The observatory is less than 2 miles from a major source of light pollution: Orlando's downtown skyline, anchored by the 24-story Orange County Courthouse. Targeted by 110 floodlights, it blazes like a flare. (The floodlights, newly converted to efficient LEDs, shut off at 11 p.m.)

In really dark places, satellites soar past throughout the night, crisscrossing, drag racing or appearing to head at one another in a type of orbital chicken.

The chaos is more interesting if viewed through a smartphone with an app that identifies each satellite. They have names such as Cosmos, Ariane or HST — the Hubble Space Telescope.

In Orlando, the only satellite most residents can see is the International Space Station. With its giant wingspan of solar panels, the station is so conspicuous that even in twilight it looks like Venus pulled up anchor and went on a cruise.

Derek Demeter, director of the Seminole State College planetarium, said some beaches and rural parts of Central Florida offer decent views of the sky at night, and there are a few top-notch spots elsewhere in the state, including Cedar Key and the Everglades.

One clear night in July, Demeter and Darden went to Harmony, a remote community in Osceola County known for its annual Dark Sky Festival. Last year, more than 8,000 people attended the event, and astronomy groups brought 50 telescopes.

With his back to the distant glow of Orlando, Demeter aimed his camera south and opened the shutter.

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